Investigators in Iredell County are still sifting the ashes of an Oct. 30 house fire that burned a garage where a Chevy Volt's battery was being charged, but Duke Energy and Progress Energy say it appears neither the plug-in car nor its plugged-in charger was to blame.

The fire sparked concern for both Charlotte-based Duke and Raleigh-based Progress, which have installed free home charging stations in pilot programs for customers who drive Volts and other electric cars.

The National Highway Traffic Safety Administration launched an investigation last week to determine the risk of fire after a Chevy Volt battery is damaged in a crash (see Road Worrier column with reader comments). Bloggers across the country have speculated that faulty plug-in technology started the Oct. 30 house fire.

Damage was estimated at $800,000 for the $1.5 million house near Mooresville, where the Volt and a Nissan SUV were destroyed. The homeowner was one of 65  customers enrolled in Duke's home-charger program.

Garland Cloer, Iredell County's chief deputy fire marshal, said it appears the fire did not start in the electric car. ... [MORE]

The National Highway Traffic Safety Administration said today it will open a formal safety defect investigation to assess the risk of fire in Chevy Volts that have been damaged in crashes.  The probe, spurred by two Chevy Volt battery fires that followed NHTSA crash tests, could mark a setback for GM and its plug-in electric hybrid car.

The announcement came a day after a Chevy Volt battery caught fire at a NHTSA test facility Thursday, one week after it had been intentionally damaged in a crash test.  It was the second battery fire after a NHTSA test this year.

The first fire, in May, broke out in a parked Volt after it had been deliberately crashed in a NHTSA test designed to measure the vehicle's ability to protect occupants from injury in a side collision. The crash damaged the car's large lithium-ion battery and ruptured the coolant line, and NHTSA blamed the fire on the damage to the battery.

NHTSA engineers attempted to recreate the May event in three separate tests last week, on Nov. 16, 17 and 18.  The battery damaged in the Nov. 18 crash test later smoked and emitted sparks.  The battery damaged in the Nov. 17 test, which was monitored later at the NHTSA testing facility, caught fire Thursday, a week later.

Chevy Volt drivers, what do you think about this? Please let me hear from you by email, and don't forget your weekday contact info.  I'll get back with you on Monday.

Meanwhile, NHTSA seeks to reassure Volt owners: ... [MORE]

Is the Triangle ready for cars that plug in? Now I'll find out if I'm ready, myself.

I’m talking with Triangle folks who have started driving Teslas and Chevy Volts, put down money for a spot on the Nissan Leaf waiting list, or converted their own gas-burners into plug-in hybrids.

And starting today, I’ll get my own chance when Progress Energy lends me a Chevy Volt to drive for a few days.

I have a lot of questions about this car. And I’m especially interested in your questions: Are you thinking about buying a Volt or a Leaf or a Prius plug-in hybrid -- or one of the other e-car options that will become available in the coming months?

Post your questions below or email me (please include full contact information, which I will not make public), and I’ll post my answers. ... [MORE]

California is where they usually hold the national confab on cars that plug in. This year Raleigh is the host city for Plug-In 2011, a four-day conference and exposition scheduled July 18-21 at the Raleigh Convention Center.

Car makers are signing up folks who want to buy plug-in hybrids and electric cars.  Are you on the list?  Do you drive a Tesla? Are you planning to buy a Nissan Leaf or a Chevy Volt?  Or even thinking about it? Or maybe you've rigged up a plug-in Prius?

If so, I'd like to speak with you for a story about the Triangle's eagerness for the e-car. Please e-mail me with your contact information, or call me at 919-829-4527.

Raleigh's new public charging stations for electric cars are a sign that the city will be ready for its share of new cars that don't need petroleum.  (See today's Road Worrier column.)

Volt, Leaf and Focus Electric drivers will be doing most of their charging at home.

But if they need the security of a charging station downtown, a place to top off the battery, they'll have a few dozen options.

The first two stations are installed on West Hargett Street -- where you pay to park but not, for now, to recharge your battery.

Progress Energy is adding a dozen Chevy Volts to its growing stock of experimental electric cars.

The Raleigh-based electric utility said today it will test 12 Chevy Volt cars in its service areas in the Carolinas and Florida. Progress will use the cars in a variety of utility service roles for two years, collecting data on driving range, recharging and other issues related to electric cars.

The sight of Progress employees zipping around town in the new Volts will provide some free marketing for Chevy's electric car. The Volts will begin to be sold commercially later this year in selected areas of the country, but the car will not be sold immediately in North Carolina.

For those who want to test drive the super-hyped super-efficient Volt, Progress will have several Volts available in downtown Raleigh this Monday at its headquarters at 400 Fayetteville Street.

The Volt also is scheduled to be shown off at IBM's Research Triangle Park campus Monday afternoon -- an acknowledgement of the role IBM's software and supercomputing played in designing the innovative vehicle.

ABB, maker of heavy duty electrical equipment, will work with General Motors to develop secondary uses for electric car batteries.

ABB's portion of the work will be handled out of its research center at N.C. State University's Centennial Campus, said spokesman Bill Rose.

The lithium ion batteries that will power the Chevy Volt and Nissan Leaf have an estimated life span of about a decade. Though they will be able to hold an electric charge, over time they will drain more quickly and become less efficient, requiring replacement with fresh batteries.

The "spent" electric batteries could supply the missing link in the nation's power grid by providing a system for storing power, a technology that has so far eluded scientists and the power industry.

General Motors has produced a video with graphics and animation to explain how the Chevrolet Volt works.

Nobody was crazy about resorting to toll-collection to build the Triangle Expressway, U.S. Rep. David Price said at Wednesday's ground-breaking ceremony (see story with dozens of reader comments).

But where else will we get the money to build new bridges and expressways?

The federal Highway Trust Fund, fueled mostly with a federal gas tax that has not been increased since 1992, is running on fumes. Congress recently approved an $8 billion bailout to make sure North Carolina and other states would get the federal road dollars promised for this fall.

“We have in the past relied on one source of revenue almost exclusively for our highway building, namely the gas tax revenue,” Price said. “It has funded highway construction, safety programs and a lot of other thngs for many, many years. …

“Now, that’s not even an option. Now the gas tax revenues simply aren’t going to do the job.”

You know the story. Our cars aren't guzzling so much gas these days, so we're paying fewer gas tax pennies per mile. ...